Normal butyl lactate



- the following manner.

- to serve as a catalyst Y Patented 'May 8, 1928.

UNITED. STATES PATENT OFFICE.

POBATION OF MARYLAND.

or manna nAu'rE, INDIANA, Assianons manna nAu'rE, INDIANA, A coauoamAL BUTYL LAcrA'rE.

No Drawing.

The present invention relates to butyl esters of lactic acid, and more particularly to the normal primary butyl ester of alpha hydroxy propionic and (fermentation lactic (1 acid) which substance has the general formula, CH CH(OH) CO 0 H, and the following structural formula on 0 H;C-(l--ii OCB:-CH|-CH:-CH1.

- The normal primary butyl alcohol ester of alpha hydroxy propionic acid, which substance will be subsequently mentioned as butyl lactate, is a water-white, colorless liquid boiling without decompositionat 1869 C. under atmospheric pressure. It is insoluble in waterand neutral to methyl orange.

Butyl lactate may be readily prepared in 100 lbs. of lactic acid is mixed with 225 lbs. of normal primary butyl alcohol, and this mixture is then distilled until the temperature of the liquid reachesthe boiling point of normal primary "butyl alcohol-1. e. 117 C. Th e purpose of this distillation is to substantially dehydrate the lactic acid. Normal primary butyl alcohol forms a constant-boiling mixture with water, this mixture containing about 30% By adding a large excess of normal primary butyl alcohol over that amount required for esterification of the alpha hydroxy propionic acid, it is thus possible to remove ractically all of the water that was intro the mixture in the aqueous lactic acid (70%) solution.

Dry hydrochloric acid gas is then bubbled into the residual mixture for about an'hour the mixturebeing refluxed. Therefluxing is continued for about two hours after the addition of hydrochloric acid gas has ceased, and the mixture is allowed to cool.

Oncooling an aqueous layer, formed during esterification and containing a major portion of the residual hydrochloric acid of water, and distilling at 92 C.

uced into I v for the esterification,

Application filed November 29, 1926, Serial 170. 151,595. Renewed FebruaryM, 1928.

passed into the mixture, the reactionmixture. This is drained off and water is added to the mixture, one uarter volume being used, to wash out traces of hydrochloric acid. The water is then drained off in a like manner. Y

The washed residue is then distilled, the

will be found'under fraction passing over at 186-9 C. being the butyl lactate thus prepared. -A yield of 7 5% of the theoretical, or better, is thus obtained. 3

Butyl lactate is soluble in or miscible with a great variety of organic liquids, such as hydrocarbons of the benzol series, aliphatic alcohols, and the aliphatic esters of the fatty acids. -It is-a solvent for nitrocellulose and for many varnish gums. On account of these properties and in view of its low rate of volatility, but llactate forms a valuable constituent of nitrocellulose lacquers. I The use of this new substance in the manner described has been claimed byns in U. S aipp lication Serial No. 31,969, filed May 21st,

.Now having having invention, we claim the novel 2- 1. As a new composition of matter, the normal primary butyl ester droxy propionic acid.

2. A composition of matter comprising a butyl ester of lactic acid whose molecular structure is expressed by the following formula:

fully described our following as new and 3. As a new composition. of matter, the normal primary butyl ester'of alpha hydroxy ropiomc acid, a colorless, water white, liquld'boiling at 1869 C.

of alpha hyand forms no part of the present 1n- 'vention.

In testimony whereof we afiix our signa- I t'ures.

CHARLES Ii. GABRIEL. CHARLES BOGIN. 

